I've designed a box I'm going to have you guys print in plastic. I've ordered a number of parts from you this way, but not for a while, and I can't remember what I'm supposed to do to help you get the powder out., Specifically, the box has .125" thick walls which, as I recall, you'll print as two, parallel, thinner walls with loose powder in between. If I don't want to pay for that powder, somehow I'm supposed to put a couple of holes in the part for you to blow it out. I'm making this in Fusion 360, though, and it doesn't let me make a hole in just one side of an object (it already has several through holes, but the .125" face of each hole is solid). Alternatively, if I'm willing to pay for the in-between powder, is there a way to insure all the powder is bound together, so the wall is solid and not two thin walls with loose powder in between? Hope this makes sense. Thanks for the help.